FOLKSTON, GA — A 39-year-old mother from Georgia fatally shot her 15-year-old son, who had Down Syndrome.

The shooting shocked Butts’ family and friends, who described her as a happy and loving mother who adored her son. But the contrast between the happy and smiling posts on social media and the gruesome crime scene at the family home near Saint George was horrific.

Police responded to a 911 call on Tuesday morning placed by Butts’ father, Mike Wilson, according to People. Wilson had gone to the home to borrow an onion.

When investigators arrived, they found Butts’ and Caleb’s lifeless bodies lying side-by-side across a bed in the master bedroom.

The dead body of Butts’ mother, Jan Kirkland, 64, was found in the hallway.

Wilson told a Charlton County 911 operator that he smelled a strong gas odor and sees several lit burners.

“I need police, detectives, and a CSI,” he said. “There are three dead people in my house.”

According to a statement by the Georgia Bureau of Investigations, “evidence currently shows that Kimberly Gayle Butts took the lives of Caleb Logan Butts and Jan Elizabeth Kirkland prior to taking her own life.”

A full medical report will be available in a few months once forensics and ballistic reports are completed, according to authorities.

Butts was unemployed and struggled with finances, according to police.

A preliminary investigation found that Caleb had been shot in the chest multiple times. Butts had a gunshot wound to the left temple, and there was a pink semiautomatic handgun resting on her left shoulder, the statement says.

Shawna Tomlinson, a family friend, told People that Butts had been dealing with back pain from a degenerative disk – and that the day before the fatal shootings Butts got into an aggressive confrontation at McDonald’s with a man who accused her of jumping the line.

Relative Sandy Dobbs told People that the family is “in shock,” adding: “She always seemed like a really bubbly person, and he always seemed like a happy child who just loved to have fun.”

In 2009, mother of two Susan Powell disappeared without a trace in West Valley City, Utah. Then in 2012, husband Josh killed himself and their two sons after custody of the children was granted to Susan's parents.